This is a reland of b7f0951f

Original change's description:
> [wasm] Add a separate CodeTracer to the WasmEngine.
> 
> This makes sure the TurboFan pipeline is independent of the Isolate by
> getting the CodeTracer from the WasmEngine for WebAssembly compilations.
> 
> R=clemensh@chromium.org
> 
> Change-Id: I343af1a2bfaeff77e2f41ef0c53fbfe165e2e202
> Reviewed-on: https://chromium-review.googlesource.com/1134997
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54455}

Change-Id: I48b161b5f35dd388fd3ef299afe04214a666b5a6
Reviewed-on: https://chromium-review.googlesource.com/1138114
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54462}